Organic light-emitting devices are devices each including an anode, a cathode, and an organic compound layer disposed between the two electrodes. Electrons and holes are injected from the electrodes to generate excitons of a luminescent organic compound in the organic compound layer, and light is emitted when the excitons return to the ground state.
The organic light-emitting devices are referred to as “organic electroluminescence devices” or “organic EL devices”.
In recent years, remarkable progress has been made in the organic light-emitting devices to permit the formation of thin and lightweight light-emitting devices having high luminance at low applied voltage, diversity in emission wavelengths, and rapid response.
The organic light-emitting devices can be used as exposure light sources for exposing photosensitive members of image display devices and electrophotographic image forming apparatuses.
Novel luminescent organic compounds have been created so far.
For example, PTL 1 discloses IK-12 shown below as an example of an organic compound constituting a light-emitting layer serving as an organic compound layer. This compound has, as a basic skeleton, benzo[k]fluoranthene shown below. The basic skeleton represents a condensed ring having a conjugated ring structure.
